CARADOC BRACHIOPODS FROM THE SHAN STATES 



111 



*Ptychopleurella sp. [0. (Ptychopleurella) cf. lapworthi: 1936: 



27, pi. 2, fig. 4]. 

 Saucrorthis irravadica (Reed, 1906) [Orthis pustulifera: 1936: 



18, pi. 1, figs 7-14, pi. 2, fig. 3]. 

 Skenidioides sp. [Skenidioides cf. billingsi: 1936: 68, pi. 2, figs 8, 



8a]. 

 *5. sp. [0. (Hesperorthis?) sp.: 1936: 20, pi. 1, fig. 19]. 

 *Indet. draboviid [0. (Dalmanella) sinchaungensis: 1936: 28, pi. 



2, figs 12- 15a]. 

 *Dalmanella? sp. [0. (D.) testudinaria shanensis: 1915: 9, pi. 2, 



figs 8, 11]. 

 Onniella chaungzonensis (Reed, 1906) [0. (D.) testudinaria: 



1906: 60, pi. 4, figs 25-26; 0. (D.) testudinaria shanensis: 



1915: 9, pi. 2, figs 6-7, 9-10]. 

 *Indet. dalmanelloids [Yeosinella consignata: 1932: 193, pi. 3, 



figs 1 la, 2; 1936: 30, pi. 4, fig. 11]. 

 Indet. clitambonitid. 

 Leptellina (Leptellina) minor sp. nov. [Leptelloidea (?Leangella) 



cf. derfelensis: 1936: 43, pi. 4, figs 24-25; L. (Leangella) cf. 



sholeshookensis: 1936: 43, pi. 4, fig. 28]. 

 *Indet leptellinids [Leptelloidea yeosinensis: 1932: 196. pi. 3, 



figs 3-6;L. campestris: 1936: 42, pi. 3, figs \6-\l\Leptestina? 



sp.: 1936:46, pi. 3. fig. 4]. 

 *Leangella (Leangella) sp. [Plectambonites cf. llandeiloensis. 



Reed 1915: 13, pi. 3, fig. 3]. 

 Bekkerella subcrateroides (Reed, 1906) [Rafinesquina 



(Bekkerella) gentilis: 1936: 38, pi. 4, fig. 14]. 

 Ishimia subdeltoidea (Reed, 1906) [R. (Kjaerina) cf. felix: 1936: 



37, pi. 4, fig. 1]. 

 Prychoglyptus? shanensis, Reed, 1932: 195, pi. 3, fig. 15. 

 *Indet. sowerbyellids [Plectambonites repanda: 1906: 56, pi. 4, 



fig. 3&:Sowerbyella cf. liliifera var. triangulum: 1936: 39, pi. 4, 



fig. 10]. 

 *Indet. plectambonitoid [Plectambonites quinquecostata: 1906: 



55, pi. 4, figs 34-35; P. sericea: 1906: 57, pi. 4, figs 36-37]. 

 Bellimurina (Bellimurina?) sp. 

 *Indet. strophomenids [Strophomena sp.: 1915: 12, pi. 3, fig. 1; 



Rafinesquina (Kjaerina) cf. praecursor: 1936: 71, pi. 3, fig. 



18]. 

 *Indet. furcitellinid [R. imbrex: 1906: 52, pi. 5, figs 9-12]. 

 Dirafinesquina globosa gen. et sp. nov. [R. cf. alternata: 1936: 



69, pi. 3, fig. 6; R. cf. semiglobosina: 1936: 70, pi. 3, fig. 7]. 

 Indet. leptaenines [Leptaena cf. juvenilis: 1936: 33, pi. 3, fig. 3;L. 



cf. richmondensis: 1936: 34, pi. 3. fig. 11; L. spectata: 1936: 



34, pi. 3, fig. 12]. 

 Glyptomena sp. 

 Indet. syntrophopsid. 

 Porambonites spp. [f! intercedens: 1906: 68, pi. 5, figs 15, 15a, 



15b; P. sinuatus: 1915: 14, pi. 3, figs 4-5; P. cf. acutiplicata: 



1936: 48, pi. 3, figs 1-2; P. cf. wahli: 1936: 49, pi. 3, fig. 15; 



Clitambonites cf. squamata: 1906: 66, pi. 5, fig. 14; C. cf. 



ascendens: 1936: 31, pi. 3, fig. 14]. 

 Protozyga? haydeni Reed, 1936: 51, pi. 4, fig. 12. 

 *Cyclospira sp. Reed, 1936: 52, pi. 4, fig. 13 [IHyattidina sp.: 



1932: 206, pi. 3. figs 17, 18]. 



In addition. Reed figured the following which we find indetermi- 

 nable, and have therefore omitted both from the above list and also 

 from our faunal analysis of palaeobiogeography (not in this list are 

 other determinations by Reed without any figures): 



Ahtiella? sp.: 1936: 47, pi. 1, fig. 20; Clitambonites cf. pyron: 

 1906: 65, pi. 5, figs 13, 13a; Chonetes? thebavensis sp. nov.: 

 1906: 57, pi. 5, fig. 16 (perhaps an orthoid); Gonambonites 



(Antigonambonites) emancipatus: 1936:67. pi. 1, fig. 25;Ingria? 

 sp.: 1936: 47, pi. 4, fig. 2; Leptaena? ledetensis sp. nov.: 1906: 

 54, pi. 4, figs 39^1 (perhaps a plectambonitoid); Leptelloidea 

 cf. leptelloides: 1936: 73, pi. 4, fig. 9; L. (Leangella?) lamellata 

 sp. nov.: 1936: 44, pi. 4, figs 22, 23, 23a (indeterminable 

 plectambonitoid); Leptestia cf. musculosa: 1 936: 45, pi. 3, fig. 8; 

 Orthis calligramma var.: 1906: 59, pi. 4, fig. 3; 1915: 1 1. pi. 2, 

 figs 14, 14a; 0. (Dalmanella) elegantula: 1906: 60, pi. 4, figs 23- 

 24; 0. (Hesperorthis) cf. tricenaria: 1936: 68, pi. 1. fig. 22; 

 (Platystrophia) biforata var.?: 1915: 10, pi. 2, fig. 15; O. 

 (Ptychopleurella) pinea sp. nov.: 1936: 26, pi. 1. figs 18, 18a 

 (indeterminable orthoid); Petroria cf. rugosa: 1932: 98, pi. 3, fig. 

 16; Protozyga? cf. obsoleta: 1936: 52, pi. 5, figs. 9-10; 

 Rafinesquina cf. jaervenis: 1936: 71, pi. 3, figs 13, 13a; R. (or 

 Leptaena) cf. nubigena: 1936: 72, pi. l.fig. 16;/?. cf. richardsoni: 

 1936: 37, pi. 3, fig. 9; Skenidioides cf. billingsi: 1936: 68, pi. 2, 

 figs 8, 8a, 16-17; S. cf. oelandicus: 1936: 30, pi. 2, figs 18-21; 

 Sowerbyella cf. cylindrica: 1936: 40, pi. 4, fig. 15; S. cf. 

 himalensis: 1936: 40, pi. 4, fig. 3; S. wilsoni sp. nov.: 1936: 41, pi. 

 4. figs 4-8 (indeterminable plectambonitoid); Stropheodonta aff. 

 corrugatella: 1915: 1 2, pi. 3, figs 2, 2a; Strophomena cf. subtenta: 

 1936: 35, pi. 3, fig. 10; S. (Actinomena) cf. subarachnoidea: 

 1936: 36, pi. 3, fig. 5; Syntrophina cf. affinis: 1936: 49, pi. 1, fig. 

 17; Vellamo nemoralis: 1936: 31, pi. 1. figs 5-6; V. cf. Isimplex: 

 1936:32, pi. l.fig. 21. 



AGE OF THE FAUNA 



From the above list, we perceive that the known fauna from the 

 Naungkangyi Group and its equivalents consists of 31 genera, 

 amongst which 32% are orthoids and 42% strophomenoids, and that 

 these two groups are also the most abundant. The absence of 

 rhynchonelloids is an outstanding character of the fauna. Besides the 

 two endemic genera. Bekkerella and Dirafinesquina, most of the 

 others are limited to the Ordovician. and mostly the Llandeilo to 

 Ashgill. Plaesiomys is widely distributed and all its occurences are 

 of Caradoc and Ashgill age, so is Nicolella, which is also found in 

 the early Caradoc Shihtzupu Formation of South China. The 

 Saucrorthis in our fauna is its first record outside South China, 

 where it is reported only from the Shihtzupu Formation. Onniella is 

 of Caradoc to Ashgill age with its acme in the Caradoc. Most of the 

 known species of Protozyga are limited to the early to middle 

 Caradoc of North America, north-west Europe and south-east Asia 

 (Copper 1986: 834). Cyclospira ranged from the Caradoc to the 

 Ashgill, and was particularly common in the late Caradoc (Copper 

 1986: 847). Ishimia is known from Llanvirn to early Caradoc rocks, 

 Prychoglyptus from the Caradoc to the Ashgill, Bellimurina only 

 from the Caradoc andGlyptomena from the Llandeilo to the Caradoc. 

 Once again, Leptellina (Leptellina), Leangella (Leangella). 

 Bellimurina, Leptaena (Leptaena) and Glyptomena are also known 

 in the Shihtzupu Formation of South China. Fortey & Cocks (1998) 

 have also discussed the age of the Upper Naungkangyi Beds. Thus 

 the faunas studied here from the Naungkangyi Group and its equiva- 

 lents in the Shan States are probably of Caradoc age. At what period 

 within the Caradoc these rocks were deposited is less certain. Any 

 age above the early Caradoc would extend upwards the ranges of 

 Saucrorthis and Ishimia. However, since the Naungkangyi Group is 

 more than 2000m thick, then a variety of ages may be represented. 

 However, in addition to the faunas discussed above, there are 

 clearly also some earlier Ordovician brachiopods occurring in the 

 Shan States. Reed (1932: 182. pi. 3. figs 7- 14) described and figured 



